Sony NEX-FS100

Camcorders that deliver a similar shallow DoF (depth of field) to 35mm film are very much ‘en-vogue’ at the moment, with manufacturers reversing the former trend of producing cameras with ever decreasing sensor sizes in favour of large sensors which accentuate the shallow depth of field.

This is the new NEX-FS100EK camera from Sony, scheduled to be available for sale slightly earlier than originally anticipated with deliveries starting at the end of May 2011. It features the Super 35mm size CMOS sensor as used in the PMW-F3, ‘nxcam’ AVCHD recording at up to 24Mb/s and an ‘E’ mount to allow attachment of a wide range of lenses / third party adaptors. At less than half the price of a PMW-F3, the FS100 is aimed to help Sony recover the ground recently lost to Canon’s HD DSLR’s as well going head-to-head with Panasonic’s recently introduced AG-AF101 (AF100) micro 4/3″ camcorder.

Here’s our ‘hands-on’ appraisal of the FS100:

Pared of all accessories, the FS100 looks rather similar to an old DSR-V10 DVCAM video walkman ‘clamshell’ recorder with a sensor and lens port grafted onto its rear end. In effect that’s exactly what it is, a super-35mm sensor equipped solid state deck with 3.5″ flip-up screen and a whole bunch of accessory mounting points. The FS100 even uses legacy NP-F type InfoLithium batteries as used on many of Sony’s professional HDV and nxcam camcorders. As standard the FS100 is supplied with a removable handgrip and a detachable handle / microphone / mount. You can buy it packaged with a Sony 18-200mm f/3,5-6,3 E-Mount zoom lens too (NEX-FS100EK) and that’s the version that Sony have kindly lent us for this review.

The first thing to note is that the camera we are reviewing is a pre-production prototype and as such it can record at 60Hz only. Whilst its build quality looks 100% customer-ready, there’s sure to be some firmware tweaks between now and the final shipping date in order to improve functionality and performance.

Sensitivity
Prior to firing up the FS100 I’d spent a whole day testing an HXR-NX70E which is an amazing piece of kit (see separate review coming soon). The NX70 has a 1/2.88″ Exmor-R sensor and F/1,8-3,5 zoom lens so for a small-sensor camera it’s very good in low light conditions – Bearing this in mind I was astounded to discover that the FS100 is vastly more light-sensitive despite the handicap of a much ‘slower’ zoom lens. In fact it’s so sensitive that it immediately highlights one of the FS100’s few shortfalls – A total lack of in-built ND (Neutral density) filters. If you’re shooting in daylight conditions without using an appropriate ND filter you’ll probably have to stop the aperture down to F/11 (or above) and this will counteract the effect of the large sensor and effectively cancel out the shallow DoF effect which is of course the whole reason you bought the FS100 in the first place! So if you buy an FS100 you simply have to buy a set of ND filters too.

Image quality
In a nutshell, the incorporation of the PMW-F3’s Super-35 CMOS image sensor the FS100 delivers a beautiful image quality that is unrivalled by anything other than the F3 itself. This means excellent light sensitivity, very low visible noise even when using high gain settings, wide dynamic range, low aliasing / moire patterning.

(Video & still image samples to follow soon)

Recording
The FS100 shares its sensor with the F3, however the similarity ends there because its signal processing is 8-bit and internal recording is AVCHD onto a single piece of SDHC / SDXC media. To comply with the AVCHD format the FS100 is restricted to a maximum data rate of 24Mb/s. Whilst this doesn’t sound very exciting, the quality of AVCHD at a given data rate is far better than could be achieved with older MPEG2 based codecs – Make no mistake, the recording quality is actually very good indeed, even at 24Mb/s. For those who want to eke the best possible quality from their FS100 then it is easy to attach an external recorder via the camera’s 8-bit HDMI output socket.

Ergonomics

The FS100’s form factor is unique for a video camera and at first glance both the LHS and top panels are literally covered in buttons, however the buttons near to the lens mount are for lens control, buttons at the rear left are for camera control and those on the top panel by the LCD are for audio control and recording / playback control. The buttons are sensibly sizd and I have had no problem in actuating any of them even with my sausage fingers! Once familiarised with the layout all the buttons are as well placed as possible and the menus are very easy to navigate (once you realise that the sub-menu marked ‘Camera Audio’ means Camera and Audio rather than Camera Audio!). The FS100 is supplied with a detachable handgrip that can be rotated about the axis of its mount point. The handgrip features a record stop / start button that is connected to the FS100 by an external cable and 3.5mm jack plug. There is no zoom rocker on the FS100 body or the handgrip, so when using a zoom lens the focal length must be set via the lens itself.

There’s a detachable ‘handle’ and microphone mount supplied with the FS100 – It’s not really a handle, more like an accessory mounting bracket that you can also use as a handle. The great thing about this bracket is that it has an array of 1/4″ and 3/8″ accessory mounting threads on all faces, aiding mounting of monitors, viewfinders, microphones, external recorders etc…

The form factor of the FS100 works very well on a tripod but is not ideal for handheld use: Serious users will undoubtedly need to invest in a third party viewfinder such as a Cineroid EVF-4L, A Zacuto EVF or a Kinotehnik LCDVFe in conjunction with a good shoulder support rig.

Standard Lens
The E-series 11x zoom lens is very versatile and features a usefully short MOD (Minimum Objective Distance), however the narrow apertures at anything other than the widest end of the zoom range really make it largely unsuitable for shallow DoF shots. At F/3,5 you can achieve some good effects, however you really do need to have the foreground very close to the lens. In general it’s easier to create a shallow DoF effect on a 2/3″ camera with a F/1,8 lens than an FS100 with the 18-200, so FS100 users will definitely need a set of wide aperture lenses such as Zeiss CP.2’s or Nikon / EOS lnses with a suitable adaptor.

I tried out the auto focus on this lens, however the result was useless with the lens perpetually hunting for the focus point. I guess this is a known issue with the prototype which will be fixed before launch… Let’s hope so, as it’s sometimes useful to use the AF function. The other was that the back-focus (flange-back) was clearly not correctly set as the lens was able to focus beyond infinity. I did not notice an adjustment for this on either the lens or the camera so again let’s hope this is fixed on the production model.

A nice feature when using Sony E-mount lenses on the FS100 is that lens settings parameters are all displayed in the viewfinder, making it easy to sanity check your focal distance.

Viewfinder
In a departure from traditional video cameras, the FS100 features a single flip-up 3.5″ LCD screen and is supplied with an extension tube / magnifying eyepiece that easily clips into place. On the top of the chassis there’s a thumbwheel to increase tension on the LCD mount and allow the viewfinder angle to maintained even when the extension tube is in place. Unfortunately the tension is only applied to the vertical axis, so the assembly readily and annoyingly wobbles from side to side when in use. I would have to devise and use an auxiliary support to prevent this, as it’s very important the eyepiece is fixed in position relative to the camera. The resolution of the screen is very good and using a combination of Peaking (focus on red) and Expanded Focus I found it very easy to achieve critical focus. When using the extension tube the viewfinder is far better than the F3’s rear viewfinder! When shooting in dark / dim conditions it’s great to be able to remove the extension tube and directly view the LCD panel. The centred position of the LCD to the rear of the camera works very well for tripod shooting and low angle shots, however because the assembly cannot be angled downwards with the extension fitted it can’t be used for high level shooting where the camera is for example above head height on a tall tripod – For that you will need an external viewfinder or monitor…

In summary
If you really can’t strech to a PMW-F3 then the FS100 offers remarkable versatility and DSLR beating performance at a bargain price point. I recommend the NEX-FS100EK version because even though the 18-200mm lens is ‘slow’ it is great value and very versatile for general shooting where a shallow DoF is not critical.

NEX-FS100E Pros & Cons:

+ Outstanding sensitivity & image quality

+ No crop factor when used with Super-35 designed lenses such as Zeiss CP.2’s

One thought on “Sony NEX-FS100”

You mention focus problems. I have them, too. Whenever there is high contrast or sharp lines in the background the camera keeps focussing on the background. There is peaking as a manual focus assist, but this does not work in low contrast areas e.g. a poorly lit face. A touch autofocus as they built into the NEX 5 would clearly help.